Don’t let the command line nature of this program scare you away. I promise it’s much easier than it might first appear. The ncdu tool, which stands for NCurses Disk Usage, is built on the ncurses library which allows for graphical interfaces within the terminal.

In fact, I find ncdu the simplest tool out of all the ones on this list. When you run it, it immediately scans your system and starts you off in the directory specified as a parameter (default is the home directory). From there, you just navigate with the cursor keys.

Several actions can be executed with single keystrokes, such as sorting by name or by size, deleting a given file or directory, toggling hidden files, showing more information on an item, etc.

Overall, this is a wonderful tool that accomplishes a lot while staying clean and minimal.

You may recognize this program by its former name, Baobab. Some time ago GNOME began to rename their default software offerings (such as when Totem was renamed to GNOME Videos), resulting in the new name Disk Usage Analyzer.

Either way, the same features that made Baobab so useful are still here, making Disk Usage Analyzer one of the better graphical tools for GNOME users.

What I like about this one is its functional simplicity. The window is split into two panels: the left side shows a tree structure that starts at the root while the right side shows a circular-but-not-quite-pie chart that color codes each element for easy discernment.

As the name states, it’s just an analyzer so there isn’t much to do in terms of interacting with files and directories as you look through your hard drives. However, if all you need is a quick way to pinpoint data usage, it’s very good.

If you’re a Windows user, you might be familiar with WinDirStat. Did you know that WinDirStat is actually a clone of a KDE tool called KDirStat? Most people think that Linux copied Windows here, but the opposite is true. Not that it really matters, though.

As one would expect from a clone situation, K4DirStat looks nearly identical to WinDirStat: a tree-based hierarchy that provides a lot of upfront information and a graphical map along the bottom that separates and clusters all files according to directory.

There isn’t much else to say. There’s a reason why K4DirStat and WinDirStat are both so popular: quick to learn, easy to use, and extremely helpful for managing disk space. If I weren’t a GNOME user, I’d be using this one as my main analysis tool for sure.

Graphical Disk Map, more commonly known as GDMap, is like K4DirStat without the tree hierarchy aspect. Most people find the lack of a tree to be unusual and uncomfortable, but if you’re in the minority and prefer a map instead, this one’s for you.

The display of proportionally-sized rectangles to represent various files and directories can be navigated extremely quickly once you get the hang of it. It makes it so you don’t even have to worry about file or directory names — the biggest shapes are using the most space.

That’s about it in terms of features. GDMap is lightweight and simple — maybe even too simple — and is the kind of application that only does one thing but does it very well.

JDiskReport is a run-of-the-mill analyzer that makes it easy to see which files and directories are the biggest culprits of disk space hoggery. In that sense, it doesn’t really accomplish all that much more than the previous tools that were already mentioned.

However, what is nifty about JDiskReport is that it offers a few different ways to view the same information. By default it displays disk space usage as a pie chart, but you can also view a Top 50 list of largest files as well as distributions according to file size and file type.

The one thing that keeps me from really loving JDiskReport is its interface. Having been written using what I assume is Java’s Swing UI, it feels unnecessarily dated. Does it impact functionality? No. Does it make me grimace? A little bit.

Final Thoughts

At the end of the day, whatever works, works. I’m hesitant to declare one of these as better than the others because they all appeal to different preferences. Use the one that meshes best with your tastes; they’ll all get the job done, anyway.

I like Disk Usage Analyser but for the one missing piece - I want to see the unused space in the chard graphically so I can see quickly what space is available on a given drive. It shows in the Devices and Locations screen but not in the pie chart. Does anyone know of a way to enable that?

For windows I still keep a copy of "SpaceMonger.exe" around. It's a simple executable that doesn't need to be installed and does show me unused space. I'd like the same in Linux however.

Thunar File Manager in Xubuntu has a popup showing percentage of disk space used when you mouseover the disk name. Right-clicking on a directory to open the properties window will show number of files and total size, along with amount of free space on the device.

Dolphin File Manager has a Status Bar that displays the number of folders and files at the level you are at, the space taken by those files and the amount of free space in the partition. The Status Bar can be toggled in Dolphin Setup.